What is hypervisor?

hypervisor is a unique type of software that allows the computer to run more than one operating system (OS). Through the process known as virtualization, the software cheats every operating system to think that it has exclusive access to a particular set of hardware. It sits between physical hardware and OS and represents a virtual set of hardware for all other software running on the machine. It also manages the flow of information between software, virtualized hardware and physical hardware. This type of software is used in consumer and business settings.

In most cases, computer axes run in a highly privileged state where it has unlimited access to the machine hardware, while the application runs in a less privileged state and has to rely on OS. These different levels of the privileges of access to hardware are known as rings, with OS traditionally running in a circle 0; User applications run in 1-3 rings that have less privileges. This model works well for most of the time when trying to start more than oneHowever, the OS on one computer will disintegrate completely. Hypervisor solves this problem using a technique called virtualization.

virtualization is not a new idea, but since mid -2000 it has been something like buzzing, because the industry and IT) have realized their potential to reduce costs and increase efficiency. There are many different approaches to virtualization, but the basic idea is to create simulated hardware sets that are often known as virtual machines. In the case of a hypervisor that can also be called a virtual machine monitor, each virtual machine contains a "visiting" operating system. The hypervisor itself can run directly on physical hardware, in which case it is known as the type of "bare metal" or in the host operating system as a "software" hypervisor.

Hypervisors must use some very sophisticintened techniques to manage its operating systems of guests and ensure thatdid not aimed each other. Since the OS inside the virtual machine is not aware that the Ring 0 has been deprived of the Ring 0, it can try to perform limited functions without permission. In these cases, the hypervisor can capture the function before reaching the hardware, instructing in a way that does not cause any damage to other operating systems running on the hardware and returns the result to the original operating system. Known as "trap and emulation" technique, it is only one of the many advanced concepts unique to the world of virtualization.

Since this type of software has become more important and lucrative, more companies were looking for ways to alleviate the load of hypervisor and provide increased performance. Software retailers have modified their operating systems so that they are aware of the virtual machines on which they run, which means fewer types of trap and emulu scenarios. Hardware suppliers have a dded for a new level of privileges sometimes known as a ring -1. Newer software programs mOhou use one or both of these techniques to increase performance.

hypervisors can now be found in various consumer and business products. Consumer products that allow to operate one operating system in another often use hypervisor software. In the enterprise space, the software enables consolidation of insufficiently used servers operating various operating systems. Software developers can use this approach to perform multiple instances of similar or even identical operating systems to test compatibility problems.